[krbdev.mit.edu #6705] plugins don't build on HP-UX

[Tom Yu via RT]

""Arlene Berry" via RT" <rt-comment at krbdev.mit.edu> writes:

> Until recently we didn't build any of them but now we're building the
> pkinit one.  The problem is that it tries to build them with a ".so"
> extension but it needs to be ".sl" for HP-UX.  I first ran into it when
> I was merging in 1.7 and never got around to reporting it.  There was a
> new plugin that we hadn't turned off which had the same problem so I
> suspect it's all of them.

I think I see some of the problems in the 1.7 branch but I will need
to investigate further.  In 1.8 and trunk, the problems should be
limited to "make clean" and some plugins that we don't compile by
default.